Special thermal electric power generating unit using pressurized hot air together with superheated steam

ABSTRACT

A thermal electric power generating unit using pressurized hot air together with superheated steam, which is useful for storing superfluous electric energy of thermal power plants in the form of compressed air during an offpeak load period and to regenerate electric power by using the thus stored compressed air during succeeding peak load periods. The unit comprises a means for producing compressed air, a boiler to produce superheated steam, a blind drum to heat the compressed air, an injection nozzle to simultaneously inject said superheated steam and the pressurized hot air from said blind drum, a gas turbine to be driven by gaseous mixture jets from said nozzle, and an electric generator driven by said gas turbine.

United States Patent lnventor Kiichi Yamada I542, l-Chome, Jingumae, Shiburja-ku, Tokyo, Japan Appl. No. 772,239 Filed Oct. 31, 1968 Patented Aug. 3. 1971 Priority Dec. 1, 1967 Japan 42/7676] SPECIAL THERMAL ELECTRIC POWER GENERATING UNIT USING PRESSURIZED 110T AIR TOGETHER WITH SUPERIIEATED STEAM 3 Claims, 5 Drawing Figs.

US. Cl 290/2, 290/52. 60/39, 60/59, 60/40 Int. Cl F02c 7/00 Field ofSearch 60/39.l3, 39.19, 36, 39, 59, 59 T, 40; 290/2, 4, 30, 30.5, 306

References Cited UNITED STATES PATENTS 8/1937 Maniscalco 60/59 X 2,124,289 7/1938 Ericson 60/59 3,086,362 4/1963 F0ster-Pegg.. 60/59 X 676,685 6/1901 Ostergren 60/39 848,027 3/1907 Beskow et al.... 60/39 1,090,523 3/1914 Farr 60/39 2,221,969 11/1940 Gonzalez". 60/40 X 2,536,062 1/1951 Kane 60/39.19 X 3,151,250 9/1964 Carlson 290/30 X Primary Examiner-G. R. Simmons Attorney-Robert E. Burns ABSTRACT: A thermal electric power generating unit using pressurized hot air together with superheated steam, which is useful for storing superfluous electric energy of thermal power plants in the form of compressed air during an offpeak load period and to regenerate electric power by using the thus stored compressed air during succeeding peak load periods. The unit comprises a means for producing compressed air, a boiler to produce superheated steam, a blind drum to heat the compressed air, an injection nozzle to simultaneously inject said superheated steam and the pressurized hot air from said blind drum, a gas turbine to be driven by gaseous mixture jets from said nozzle, and an electric generator driven by said gas turbine.

PATENTED AUG 31911 SHEET 2 OF 4 1 U HI I I IHI I IH um J llllll lll41l llllllll INVENTOR ATTORNEY Wm slam 3,597,621

SHEET 3 OF 4 IN VENTOR ATTORNEY PATENTEDAUB 3m: (3,597,621

SHEET '4 OF 4 INVENT OR ATTORNEY SPE CiAlL THERMAL ELECTRIC POWER GENERATING lUNi'll iJSllNG PERIESSlUlRTZlElD HOT AER TOGETHER WTTH SUPERHEATED STEAM This invention generally relates to a thermal electric power generating unit, and more particularly to a special thermal electric power generating unit using pressurized hot air together with superheated steam.

it is an object of the present invention to provide a special electric power generating unit, which enables the storage of superfluous electric power from conventional thermal power plants, such as midnight output, in the form of compressed air in a tank by driving a pneumatic turbine or an air compressor by using such surplus power, so that electric power can be" regenerated by using the thus stored compressed air during peak period, such as daytime when the demand for electric power is high. With the electric power generating unit according to the present invention, the stored compressed air is conveyed to a special blind drum in the firebox ofa boiler through piping at a certain rate, while suitably regulating the pressure of the compressed air, so that pressurized hot air can be produced. Superheated steam delivered from a boiler, or a superheated steam generating chamber thereof, is injected through a special nozzle together with said pressurized hot air, so as to produce a superheated gaseous mixture jet which strikes the runner of a gas turbine to rotate it at a high speed. By driving an electric generator by such gas turbine, electric power can be produced. lt is, of course, possible to generate electric power not only during daytime but also at night by using the special thermal electric power generating unit using pressurized hot air together with superheated steam according to the present invention.

For a better understanding of the invention, reference is made to the accompanying drawings, in which:

FIG. i is a schematic plan view of a thermal electric power generating unit according to the present invention;

FIG. 2 is a side view ofthe unit;

FIG. 3 is a rear view ofa boiler used in the unit;

FIG. 4 is a vertical sectional view ofthe boiler; and

FIG. 5 is an enlarged schematic side view of an electric generator portion ofthe unit.

Like parts are designated by like numerals and symbols throughout the drawings.

Referring to the figures, a boiler ll hasa firebox 2 and blind drums 3 disposed in the firebox 2,-which blind drums 3 are used for heating compressed air. The boiler ll also has cham-' bers 4 for generating superheated steam at a certain pressure and at a certain temperature. The blind drums 3 act to generate pressurized hot air ofthe same pressure and the same temperature as those of said superheated steam. The superheated steam is delivered to a pipe 5, which conveys the superheated steam to a special nozzle 6 where the superheated steam is mixed with the pressurized hot air to produce a superheated gaseous mixture. The special nozzle 6 injects both the superheated steam and the pressurized hot air at a suitable rate toward a runner of gas turbine 7, so as to rotate the gas turbine 7 at a high speed. By connecting the gas turbine 7 to.

an electric generator 8, electric energy can be generated in response to the rotation ofthe turbine 7.

When compressed air is heated to 300 C., the compressed air is expanded to a volume more than twice as large as its original volume, and becomes pressurized hot air. In a preferred embodiment of the present invention, the pressure and the temperature of such pressurized hot air are so adjusted as to become the same as the corresponding pressure and the temperature ofthe superheated steam from the pipe 5, and the pressurized hot air thus adjusted is then fed to the spe cial nozzle 6 and it is mixed with the superheated steam therein.

The inventor disclosed a special prime mover, in his Japanese Pat. No. l92,668, titled A Speciallntensive Prime Mover of Offset Output Type," which prime mover is generally designated as 9 in FIG. 1. By rotating a pneumatic turbine with such special prime mover connected thereto, compressed air can be produced at a very low cost, because an extremely inexpensive energy source is available. The com pressed air thus produced is stored in a compressed air tank 110. A known air compressor 11 is provided for producing compressed air by using surplus power from thermal power plants during midnight, so as to store the surplus energy in the form of compressed air filled in the compressed air tank 10. In the illustrated embodiment of the invention, both the special prime mover 9 and the known air compressor 11 are used, but it is also possible to dispense with one of them in the unit of the invention.

If the compressed air stored in the tank 10 is used for generating electric power during daytime when the demand for electric power is high, the thermal power plant can be efficiently operated day and night with full output, so that the equipment of the thermal power plant is fully utilized and the cost of the electric power generated can be reduced.

The illustrated embodiment of the present invention further comprises a blower 12, another compressed air tank 13, a motor 14, pipes ll5, 16 for feeding the pressurized hot air, a pneumatic turbine 17, another motor 18, a water pump 19 driven by a motor 20, a water supply pipe 21, a steam condenser 22, another water pump 23 driven by a motor 24, a fuel tank 25, an oil pump 26, and an injection nozzle 27.

For storing electric energy, storage batteries have heretofore been utilized. In addition, for effectively utilizing the surplus midnight output power from thermal power plants,

hydraulic pumping-up power stations have been constructed these years. However, such pumping-up power stations have numerous difficulties in the equipment thereof. In comparing the electric power generating unit according to the present invention with known thermal. power generating units, the amount of steam to be used in the former unit is less than one half of that in the latter-unit. Thus, the fuel for power generation, such as heavy oil and coal, can be saved by more than 50 percent. Furthermore, the electric power generating unit according to the present invention can be constructed together with known thermal power plants as a compound plant. The unit of the present invention can be constructed in a short period of time, and accordingly, its construction cost is low.- As compared with any known steam power plants, and the electric power generating unit of the present invention is superior in safety, economy, and freedom from public nuisance.

At the present, electric utility organizations in many countries operate their generating facilities in full during daytime to meet the demand for electric power, but more than 50 percent ofthe generating facilities become idle at night. Recently, such idle generating facilities are operated at night to run hydraulic pumping-up power stations, but such hydraulic pumping-up power stations have a considerable amount of inherent energy loss. in addition, the construction of hydraulic pumping-up power stations needs a huge capital investment. On the other hand, the unit according to the present invention serves for the purpose of highly efficient energy storage and regeneration thereof. It is an important feature of the invention that the superfluous output from thermal power plants can be stored and regenerated at a limited capital expenditure.-

lt is, of course, possible to incorporate suitable relay means in the unit of the invention, so that each offpeak load is detected for automatically actuating the air compressor for storing energy and each peak load is detected for regenerating power out of the compressed air.

What I claim is:

1. A thermal electric power generating unit using pressurized hot air together with superheated steam, comprising air compressor means; means coupling surplus output energy from a thermal power plant to saidcompressor means to operate said compressor means; first tank means coupled to said compressor means for storing air compressed by said compressor meansyboiler means having a firebox disposedtherein for heating said boiler means, second tank means for storing compressed air, a blower connected to said second tank means for supplying compressed air thereto, a fuel source, a pump connected to said fuel source, nozzle means having an output connected to said firebox, and having two inputs coupled respectively to said second tank means and said pump, for supplying a fuel-air mixture to said firebox, a plurality of steam chambers disposed therein, externally of said firebox, for producing superheated steam, a first motor-pump combination having said pump connected to said chambers for supplying water thereto, an output connected to said steam chambers, and blind drum means disposed within said firebox; piping means for conveying said compressed air from said tank means to said blind drum means in which said compressed air is heated; an injection nozzle connected to said boiler means output and said blind drum means to simultaneously discharge both said superheated steam and said heated compressed air in the form of superheated gaseous mixture jet; a gas turbine having a runner positioned with relation to said nozzle to be driven by said superheated gaseous mixture jet; a steam condenser connected to said turbine and a second motor pump combination having said pump connected between said steam condenser and said chambers for pumping water from said steam condenser to said chamber; and an electric generator connected with said gas turbine to generate electric power in response to the rotation of said gas turbine.

2. A thermal electric power generating unit according to claim I, wherein said air compressing means is a pneumatic turbine.

3. A thermal electric power generating unit according to claim 1, wherein said air compressing means is an electrically driven air compressor, and wherein said means for coupling surplus output energy includes means for coupling electrical energy for driving said air compressor. 

1. A thermal electric power generating unit using pressurized hot air together with superheated steam, comprising air compressor means; means coupling surplus output energy from a thermal power plant to said compressor means to operate said compressor means; first tank means coupled to said compressor means for storing air compressed by said compressor means; boiler means having a firebox disposed therein for heating said boiler means, second tank means for storing compressed air, a blower connected to said second tank means for supplying compressed air thereto, a fuel source, a pump connected to said fuel source, nozzle means having an output connected to said firebox, and having two inputs coupled respectively to said second tank means and said pump, for supplying a fuel-air mixture to said firebox, a plurality of steam chambers disposed therein, externally of said firebox, for producing superheated steam, a first motor-pump combination having said pump connected to said chambers for supplying water thereto, an output connected to said steam chambers, and blind drum means disposed within said firebox; piping means for conveying said compressed air from said tank means to said blind drum means in which said compressed air is heated; an injection nozzle connected to said boiler means output and said blind drum means to simultaneously discharge both said superheated steam and said heated compressed air in the form of superheated gaseous mixture jet; a gas turbine having a runner positioned with relation to said nozzle to be driven by said superheated gaseous mixture jet; a steam condenser connected to said turbine and a second motor pump combination having said pump connected between said steam condenser and said chambers for pumping water from said steam condenser to said chamber; and an electric generator connected with said gas turbine to generate electric power in response to the rotation of said gas turbine.
 2. A thermal electric power generating unit according to claim 1, wherein said air compressing means is a pneumatic turbine.
 3. A thermal electric power generating unit according to claim 1, wherein said air compressing means is an electrically driven air compressor, and wherein said means for coupling surplus output energy includes means for coupling electrical energy for driving said air compressor. 